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3 years ago

Solve the system by the elimination method 7x+5y=-25 5x+3y=-23

Mathematics

1 answer:

aksik [14]3 years ago

5 0

Step-by-step explanation:

7x+5y=25 ×3 7×-1.5+5y=25

5x+3y= -23 ×5 -10.5 +5y =25

5y= 25 + 10.5

21x+15y=75 5y= 35.5

25x+15y=69 y= 7.1

-4x=6

x=-1.5

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Match each pair of points to the equation of the line that is parallel to the line passing through the points.

Luba_88 [7]

Answer:

$B(5,2) \:\: C(7,-5) \:\: \rightarrow y=-3.5x-15$

$D(11,6)\:\: E(5,9)\:\: \rightarrow y=-0.5x-3$

$H(4,4)\:\: I(8,9) \:\: \rightarrow y=1.25x+4$

$L(5,-7)\:\: M(4,-12)\:\: \rightarrow y=5x+9$

Step-by-step explanation:

We need to match the slope of the function with the slope of the lines connecting the two points given. The slope of the lines are as follows:

$B(5,2) \:\: C(7,-5)=\frac{2--5}{5-7} =-3.5$

$D(11,6)\:\: E(5,9)=\frac{6-9}{11-5} =-0.5$

$H(4,4)\:\: I(8,9)=\frac{4-9}{4-8} =1.25$

$L(5,-7)\:\: M(4,-12)=\frac{-7--12}{5-4} =5$

$F(-7,12)\:\: G(3,-8)=\frac{12--8}{-7-3}=-2$

$J(7,2)\:\:K(-9,8) =\frac{2-8}{7--9} =-0.375$

Now,

the slope of the line BC matches with the slope of y=-3.5x-15.

the slope of the line DE matches with the slope of y=-0.5x-3.

the slope of the line HI matches with the slope of y=1.25x+4.

the slope of the line LM matches with the slope of y=5x+9.

and the slopes of the lines FG and JK do not match with any of the functions given.

Thus,

$B(5,2) \:\: C(7,-5) \:\: \rightarrow y=-3.5x-15$

$D(11,6)\:\: E(5,9)\:\: \rightarrow y=-0.5x-3$

$H(4,4)\:\: I(8,9) \:\: \rightarrow y=1.25x+4$

$L(5,-7)\:\: M(4,-12)\:\: \rightarrow y=5x+9$

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3 years ago

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What’s 50 1/3+ 50 1/3?

slega [8]

Answer:

100 2/3

Step-by-step explanation:

50+50=100

1/3+1/3=2/3

100+2/3= 100 2/3

4 0

3 years ago

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A window has the shape of a rectangle with a semicircle at the top.

Sidana [21]

Answer:

8+pi/2

Step-by-step explanation:

The area of the rectangle on the bottom is 8, or 2*4. The area of the top is half (because it's a semi circle) of pi*r^2, or just 1/2 pi

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Step-by-step explanation:

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Solutions to 4x- 8x-90

Butoxors [25]

Answer:

Step-by-step explanation:

4x- 8x-90

= -4x - 90

= -2(2x + 45)

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